Injection Sites - a Look Under the Hide

John Schnackel, DVM 8138 Scenic Ridge Dr., Fort Collins, CO 80528

Abstract to inform producers and veterinarians of problems being found at harvest, at the retail level, and by consumers. Cattle are injected with a variety of animal health Recommendations for giving proper injections were products including vaccines, bacterins, antibiotics, an­ developed. Pharmaceutical and biological companies thelmintics, analgesics, and vitamins. Giving proper were encouraged to develop tissue friendly products injections improves animal welfare, product response, and routes of administration. Many companies did the and beef quality. Current Beef Quality Assurance (BQA) research necessary to add the subcutaneous (SQ or SC) recommendations are to give products in the neck. Injec­ route of administration to a product's label and to de­ tions should be four or more inches apart. No more than velop more tissue friendly products, such as clostridial 10 mL of a product should be given at any one injection bacterins/toxoids. Some of the more irritating products site when giving products labeled for intramuscular were removed from the market place. These educational administration; label instructions should be carefully efforts, along with improved products, have reduced, but followed when administering products labeled for sub­ not eliminated injection lesions being found at slaughter cutaneous use. When given a choice, the subcutaneous or meat cutting operations. route of administration should be used. Needles should be sharp and changed often. Damaged needles should Injection Triangle be discarded. Veterinarians, technicians, and others giving injections should follow BQA recommendations. Injections should be given in the neck in the "in­ jection triangle". The lower boundary of the injection Resume triangle is above the cervical vertebrae, which lie in the middle of the neck. The upper boundary is below the Les bovins sont injectes avec divers produits de nuchal ligament, which is two to three inches (5 to 7.5 sante animale incluant des vaccins, des bacterines, des cm) below the top line. The posterior boundary is in front antibiotiques, des anthelmintiques, des analgesiques of the slope of the shoulder. This leaves a fairly limited et des vitamines. Lorsqu'appropriees, les injections area for injections. Giving injections in the neck keeps ameliorent le bien-etre animal, la reponse au produit et them out of the more valuable areas of the carcass, such la qualite du bamf. Les recommandations actuelles du as the top butt and round. Both SQ and intramuscular Beef Quality Assurance (BQA) insistent pour injecter les (IM) injections are recommended to be given in the injec­ produits dans le cou. Les injections devraient etre espa­ tion triangle. _cees d'au moins quatre pouces. On ne devrait pas injecter The nuchal ligament lies at the top of the neck plus de 10 mL d'un produit par site d'injection lorsqu'on and helps support the animal's head. The ligament has donne des produits homologues pour !'injection intra­ limited blood supply, and should be avoided when giving musculaire. Les instructions sur !'etiquette devraient injections because some products may not be absorbed etre suivies scrupuleusement lorsqu'on administre des properly. Any irritation caused by a vaccine or pharma­ produits homologues pour !'injection sous-cutanee. Face ceutical could adversely affect how an animal moves its a un choix, la voie d'administration sous-cutanee devrait head and neck. The cervical vertebrae lie in the middle primer. Les aiguilles doivent etre pointues et changees part of the neck. The vertebrae take up a significant part souvent. Les aiguilles endommagees devraient etre of the neck and are as wide as a fist. There is very little jetees. Les medecins veterinaires, les techniciens et les muscle on the lateral side of the vertebrae, so giving an autres personnes qui donnent des injections devraient IM injection into the vertebral muscles should be avoided. suivre les recommandations du BQA. The two main muscles for IM injections in the neck are triangular in shape. These muscles are wider toward Introduction the shoulder and thinner toward the animal's head. Be­ sides being wider near the shoulder, the muscles are also Nearly 20 years ago, USDA-FSIS, the National thicker here. The small size of the neck muscles limits Cattlemen's Association and others began efforts to the area in which IM injections can be given. reduce lesions found at slaughter, often in the more In front of the point of the shoulder is the pres­ expensive cuts of beef. Beef Quality Assurance (BQA) capular lymph node. Lymph nodes are found throughout meetings and other educational efforts were undertaken the body and are important for developing an immune

170 THE AABP PROCEEDINGS-VOL. 43 response. The lymph node can get bruised by an animal a single site in the hind leg can cause a significant lesion. coming into a chute rapidly and hitting the headgate Two weeks post injection of oxytetracycline, a florescent too hard. Bruising the lymph node could compromise green lesion can be found several inches above and below its ability to develop the expected immune response fol­ the injection site. Muscle lesions found at the packing lowing vaccination. plant will result in removal of the lesion and a large Many working facilities don't make it easy to give amount of surrounding muscle. Deep muscle lesions injections in the neck. In some facilities, the headgate not discovered at the packing plant, may not be found has been attached to an alley resulting in limited access until the retailer starts cutting steaks or roasts. Even to the neck. Older livestock chutes may not offer easy after deep muscle lesions are removed, tenderness of the access to the neck because of bar placement; also some remaining muscle can be adversely affected. headgates may have had neck extenders added. Dairy cows and heifers are often given injections while in SQ Injections multiple head lockups. Out of habit and convenience, BQA guidelines do not restrict SQ injections to products are often administered by "tailing" the animal 10 mL per site. For example, the label for enrofloxacin and injecting in the posterior hind leg or top butt. allows up to 20 mL to be given in one location. If not Scarring of muscle tissue may occur following IM · specified on the label, restrict the dose volume to 10 mL. injections, but when given in the injection triangle, It is important for producers, veterinarians, and techni­ less-valuable cuts of beef are affected. Again, the lower cians to familiarize themselves with product labels. boundary of the injection triangle is formed by the cervi­ cal vertebrae, the upper boundary is the nuchal ligament, SQ and IM Injections and the posterior boundary is in front of the shoulder. If the product is labeled for both IM and SQ admin­ Multiple Injections Should be at Least Four istration, the SQ route is preferred. This reduces the Inches Apart chance of causing lesions in the muscle. Should some scar tissue develop after a SC injection, it can be easily When administering multiple injections, they trimmed during hide removal. should be at least four inches (10 cm) apart. If two in­ When administering a SQ injection, a 16- or jections are to be given in the same side of the neck, one 18-gauge, 5/8-inch (16 mm) needle is a good choice. An injection needs to be given in the front part of the injec­ 18-gauge needle should be used in a lighter-muscled tion triangle, and the second injection at least a hand's animal, and a 16-gauge for heavier animals. How far width behind the first injection. This reduces the chance the needle goes through the skin is important. The cu­ of the products interfering with each other and not work­ taneous muscle tightly adheres to the skin. Even with ing properly. Spacing products apart also reduces the a 5/8-inch needle, it is easy to get into this muscle by potential for both products causing an increased reaction accident when giving a SQ injection. in the tissues. I recall a situation where a rancher's There are two methods to administer a SQ injection. son gave two oil-adjuvanted bacterins nearly on top of One would be to go through the skin at an angle; pull each other, resulting in softball-sized lesions. Follow-up the needle back out of the muscle and give the injection. investigation demonstrated that nether product caused The second method to give a SQ injection is the 'tent' significant lesions when given separately, but swelling method. The skin is pulled up by hand and the injection occurred when given too close together. is placed in the space that is created. When using the tent method, the animal needs to be properly restrained Maximum Volume at each Injection Site so the person giving the injection doesn't risk injecting the hand forming the tent. IM Injections For intramuscular injections, a one-inch (2.54 cm) No more than 10 mL of any product should be given or longer needle is indicated. Use an 18-gauge needle at any one injection site when an animal health product in lighter animals and a 16-gauge in heavier-muscled is administered IM. A smaller volume should be given to animals. Intramuscular injections in the neck should go lighter calves. Injecting more than 10 mL at one site may into the muscles which lie beneath the cutaneous muscle. decrease the product's efficacy because of the potential for reduced absorption. If a product is irritating, tissue Other Injection Areas damage may be minimized by using a smaller volume. When treating heavier animals such as bulls or Sometimes SQ injections are given behind the elbow cows, some producers and veterinarians find it more con­ over the ribs. Care must be taken not to be too close to venient to give more than 10 mL at one site. For example, the "armpit", where a product could cause inflammation IM administration of 20 mL oflong-acting tetracycline in or an infection that adversely affects nerves and blood

AUGUST 2010 171 vessels located in this area. This could result in signifi­ • Care and Husbandry Practices cant trim at the packing plant. • Feedstuffs and Sources Sometimes the "top butt" has been used for giving • Feed Additives and Medications IM injections. The top butt is not a good place to give • Processing/Treatment Records an IM injection because it is in the middle of a more • Injectable Animal Health Products valuable cut of meat. Non-steroidal anti-inflammatory drugs (NSAID), prostaglandins, or vitamins ADE are Conclusions drugs that are sometimes given in the top butt or round. These drugs have been associated with lesions in the In summary, injection guidelines are: muscle, and could adversely affect muscle tenderness 1. Give all injections in front of the shoulder where surrounding the injection. Flunixin meglumine is a the lower-value meat cuts are located. NSAID labeled for use in cattle, but only the intravenous 2. Multiple injections should be given at least four route of administration is approved by the FDA. Label inches apart. directions for administration should always be followed. 3. No more than 10 mL should be given when using the IM route. When using the SQ route, follow Change Needles Often label instructions for the volume administered at each site. If not specified on the label, restrict To reduce damage to the muscle, it is recom­ the volume to 10 mL. mended that needles be changed often. Only sharp 4. Use the most "carcass-friendly" route of admin­ needles should be used for giving an injection. Dull or istration. If the product has an option of IM or worn needles cause more tissue damage to the hide and SQ, the SQ route should be chosen. muscle. Needles should be changed at least every time 5. Change needles often - after every 10 or 15 injec­ a syringe is refilled. tions; sooner if the needle becomes damaged or If a needle becomes bent, never straighten it and dull. continue to use it because the needle has been weakened and could easily break off in the animal. A broken needle By utilizing BQA practices, animal welfare and 0 "d left in the muscle can cause a significant product defect. consumer's satisfaction of beef is enhanced. Following ('[) Also, burred needles should be replaced immediately. these guidelines should help keep injection site defects ~ ~ (') Beef Quality Assurance is the responsibility of every out of the beef supply. (') ('[) cattle producer and veterinarian. The proper adminis­ en en tration of animal health products is only one component Reference 8-:r:n of a complete BQA program. Other components of the q- National Cattlemen's Beef Association 1 BQA program 1. Ruppert R: Update on the National BQA Program. Used with permission. [ include: o· p

172 THE AABP PROCEEDINGS-VOL. 43